Sheet-metal can



(No Model.)

J. LEE. SHEET METAL CAN.

No. 537,162. Patented Apr. 9, 1895.

FIG.I

.Wrr/vcss :s:

5 mudaa Em/ 1'2 W k Hm ,4 rrofiA/ rs.

m: NORRIS PEYERS 0o, PHOTO-LITHO., Msums'rou, D. b.

NITED ST "res PATENT OFFICE,

JOHN LEE, OF SAN MATEO, CALIFORNIA.

SH EET-M ETAL CAN.

SPECIFICATION forming part of Letters Patent No. 537,162, dated April 9,1895.

' Application filed December 13, 1894. Serial No. 531,633- (No model.) 7

To aZZ whom it may concern:

Be it known that I, JOHN LEE, a citizen of the United States, residingin San Mateo, in the county of San Mateo and State of California, haveinvented a new and useful Improvement in Sheet-Metal Cans, of which thefollowing is aspecification.

My invention relates to sheet metal cans, and more particularly to theconstruction of what is known as tearing strip or key open-' ing cans.Heretofore these tearing strip or key opening cans have usually beenmade by providing the body or head portion of the can with a tearingstrip marked off or bounded by one or more scores, beads or weakenedlines along which the strip tears or separates;

the tearing strip being furnished with a pro jecting tongue to start thewinding. This projecting tongue is usually made integral with thetearing strip, but it has sometimes been made of a separate short piecesoldered to the tearing strip. The provision of the can with weakenedlines to mark oi the tearing strip'requires aspecial operation in themanufacture of the can, thus adding materially to the cost ofmanufacture; and the provision of the projecting tongue,'if it be madeintegral with the tearing strip, requires a special construction of canmaking machinery and dies, and also adds considerably to the amount ofstock or tin plate required to make the cans; and if the tongues aremade in a separate piece the soldering of the same in place is asomewhat slow and expensive operation, requiring care to prevent thestrip being soldered fast throughout its whole length, and unlessspecially located interfering with the usu'al'rapid and inexpensivemethod of soldering the end and side seams of the can itself; and thescored or weakened lines in the can frequently so diminish the strengthof the cans as to cause them to burst in the processing, or to renderthemliable to injury in handling and shipment, especially if theweakened lines are not formed with the greatest care,

The object of my invention is to provide a key opening can of a simple,cheap and practical construction; which may be open ed easily andperfectly by winding a tearing strip around a key; in which the fullstrength of the ordinary can will be preserved; which requires nospecial seore, beads or weakened lines to enable the can to be opened;which may be made by the ordinary dies, machinery and processes ofmanufacture; and in which the separate projecting tongue may be solderedin place by the same operation by which the head itself is soldered tothe body.

I have discovered, and herein my invention consists, that the ordinaryright angle flange of the can head, which fits outside the can body,will of itself, without any special provision or scores or weakenedlines serve perfectly as a tearing strip; and that the same willseparate perfectly and naturally at the corner between said flange andthe flat or disk portion of the head. I find also that a separate tongueto begin the winding may be conveniently attached and soldered in placeat the same'ti me the head is soldered to the body in the usual mannerby rolling in an inclined position through a bath of molten solder, bythe simple expedient of making the tongue of a partially tinned andpartially untinned strip, so that the untinned portion which projectsoutside will not be soldered fast to the periphery of the can, while thetinned portion will be soldered fast. By this simple expedient I seenrely and properly solder the tongue in place by one and the sameoperation with that employed for soldering the head to the body andwithout any additional expense or labor. In utilizing the exteriorflange of the can head as the tearing strip, the key around which thisflange or strip is being wound is held at an angle to the axis of thecan, so as to cause the lower or free edge of this flange or strip toseparate from the body in advance of the upper edge of this flange orstrip where it separates from the flat or disk portion of the head. Thiscauses the tearing to be done by a kind of shearing action, and preventsany tendency of the strip to run out. By separating the lower edge ofthe strip first,-or in advance of its upper edge the tendency is tocause the line of tear to run or-incline in the opposite direction fromthe free edge-of the strip, that is to say, to run or incline toward theflat or disk portion of the head; and as the line of tear thus tendingto run or incline toward the disk cannot run into the circular diskportion of the head,.it of course follows that the flange or strip mustcontinually sepa- ICO rate at the corner between the flange and citculardisk portion of the head.

In practicing my invention I make the corner uniting the flange and diskof the head as near a right angle corner as can conveniently be done,that is to say, I prefer not to make the corner greatly rounded, as issometimes done in the making of cans.

Myinvention also consists in the novel devices and novel combinations ofparts and devices herein shown and described and more particularlypointed out in the claims.

In the accompanying drawings, which form a part of this specification,and in which similar letters of reference indicate like parts throughoutall the figures, Figure 1 is a perspective view of a can embodying myinvention. Fig. 2 is a similar view illustrating the method of openingthe can by winding the flange of the head about a key held at an angleor inclination to the axis of the can. Fig. 3 is a detail sectional viewon line 3-3 of Fig. 1. Fig. at is a detail sectional view at rightangles to the axis of the can. Fig. 5 is a dctail plan view of theseparate tongue strip, the shaded portion indicating the black oruntinned part and the plain portion indicating the tinned part of thetongue strip; and Fig. 6 is a detail perspective view illustrating themethod or process of soldering the separate tongue strip in place by theact of soldering the end seam of the can in the usual manner by rollingthe can through a solder bath.

In the drawings, A represents the can body and B the can head, the samebeing furnished with the usual flange h fitting outside the body. Thecan head flange I) is provided at one point with a slit or cut 1) acrossthe same, at which the separate tongue D is inserted between the canhead flange and can body, leaving a portion (Z of the tongue stripprojecting outside for attachment to the key F to start the winding. Theportion (1 of the tearing strip D which is inserted between the flangeof the can head and the can body, is tinned or otherwise prepared sothat it may he soldered to the can head and body, and make a perfectclosure. The portion (2 of the tongue D however, which projects outsideand is to remain free from the can so that the key may be convenientlyapplied is of plain or untinned sheet steel or iron or otherwiseprepared, so that when the end seam of the can is rolled in a bath ofmolten solder or otherwise brought in contact with the solder in the actof soldering the head to the body, this outside untinned portion of thetongue D will not take the solder or be soldered to the exterior surfaceof the can. I am thus enabled by the simple act of soldering the headand body together to also at the same time solder the separate tongue Din place, and leave its projecting end (Z entirely free and unattached;and this without any extra care or expense.

To limit the extent to which the tongue D may be inserted in the slit1), I preferably provide itwith a shoulder or offset (1 and the flange bof the can head may also be preferably provided with a slight offset,shoulder or pocket 6 to receive the tongue strip. 0rdinarily thefrictional fit, bite or clamping action between the flange of the canhead and the can body, especially if the can heads are made tightfitting, as they should be, will be sullicient in itself to properlyhold or clamp the tongue strip D in place during the soldcring operationor until it is soldered fast; but if preferred the strip D may beadditionally secured to the flange Z) by piercing and clinching theparts together, as indicated in Fig. t at 1)" b The can head B is alsopreferably provided with the usual countersunk portion b but the portionL" which is united by the corner b with the flange I) should be a flatplain disk, as indicated in the drawings.

By simply holding the key F at an angle to the axis of thecan during thewinding operation, as indicated in Fig. 2, the lower free edge 0 of theflange I) will separate from the bodyA of the can in advance of theupper or corner edge I) of the flange; but this same method of tearingthe flange from the can by causing its free or lower edge to separate inadvance of its upper edge, may be effected in other ways, as for exampleby making the key tapering.

I do not herein claim the process of soldering a tongue strip to atearing strip, or the process of soldering the tongue strip and can headto the can body; and I desire to reserve the same for the subject of aseparate application.

By thus utilizing the corner, or change in direction, between thecylindrical flange of the can head and the flat or disk portion of thehead, itself, as the line of separation for the tongued tearing strip, Ientirely avoid the necessity for weakening the can with any specialscore or weakened line. It will of course be understood that this corneror change in direction between the flange of the head and the diskportion thereof is necessarily present in all cans having outsidefitting flanged heads; and while it may be true that the act of makingor drawing up such flanged heads may slightly weaken the strength of thestock in the flange, and possibly also to some extent, too, at thecorner where the drawing operation terminates and is less severe; still,as this slight weakening is only the ordinary-weakening of such flangeor corner incident to every can including those having no self openingconstruction or tongued tearing strip of any kind, it will of course beunderstood that by use of the words unscoret unweakened, no score orweakened line I do not mean thereby the slight weakening incident to thebending of the stock to give the necessary change of direction or toform the corner between the disk and flange of the head. Nor do I meanthereby that the head of my can has not the ordinary right angle flangeand the ordinary corner uniting such flange with the flat disk- I domean by these words is what is ordinarily understood by those skilled inthe art, viz: the usual special scores or weakened lines heretoforeemployed for marking off the tearing strip.

In my can, while it may possibly be truethat the stock may be slightlyweakened at the corner uniting the flange and the disk portion of thehead, it is really the right angle change in direction between thecylindrical head and the disk, and the rigid support given by the edgeof the disk directly at the line of separation to the key and coil inthe act of winding the flange about the key and separating the flangefrom the disk, which, I think, enables such corner or change ofdirection to serve without any special score or special weakening as anefficient line of separation for a tearing strip. At least this is thebest explanation I am now able to give of the reason why my inventiondoes actually operate, and since making the discovery I have given someconsiderable time, study and experimenting to the matter. My experimentslead me to believe that if the flange of the head is formed or could beformed without weakening the stock at all at the corner, the corner maybe utilized just the same as an efficient line of separation.

I claim- 1. A. sheet metal can having no score or weakened line andcomprising the body A and head B furnished with a flange b fittingoutside of the body and soldered thereto, said can head flange I) beingprovided with a projecting tongue and serving itself as a tearing stripfor opening the can, by separating from the flat or disk portion of thehead at the corner uniting the flange therewith, substantially asspecified.

2. The combination with can body A of head B having outside fittingflange b furnished with a slit or cut across the same, said head Bhaving no scored or weakened line and a separate tongue strip D in partinserted between the flange of the can headand the can body and solderedthereto, the corner uniting the flange of the head with the flange ordisk portion thereof, itself, serving as the 'line of separation of theflange from the head in coiling said flange as a tearing strip aroundthe key substantially as specified.

3. The combination with a can body A of head B having outside fittingflange b furnished with a slit or cut across the same, said head Bhaving no scored or weakened line and a separate tongue strip D in partinserted between the flange of the can head and the can body andsoldered thereto, the outside portion of said tongue strip beinguntinned and the inside portion tinned, the corner uniting the flange ofthe head with the flange or disk portion thereof, itself, serving as theline of separation of the flange from the head in coiling said flange asa tearing strip around the key substantially as specified.

4..The combination with can body A of head B having outside fittingflange b furnished with a slit or cut across the same, said head Bhaving no scored or weakened line and a separate tongue stripD in partinserted between the flange of the can head and the can body andsoldered thereto, said tongue strip and can head flange being piercedand clinched together, the simple corner uniting the flange and the flator disk portion of the head itself serving as the line of separationsubstantially as specified.

5. The combination with can body A of head B havingoutside fittingflange b furnished with a slit or cut across the same, said head Bhaving no scored or weakened line and a separate tongue strip D in partinserted between the flange of the can head and the can body andsoldered thereto, said tongue strip D being provided with an offset dthe simple corner uniting the flange and the flat or disk portion of thehead itself serving as the line of separation substantially asspecified.

6. The combination with can body A of head B having outside fittingflangeb furnished with a slit or cut across the same, said head B havingno scored or weakened line and a separate tongue strip D in partinserted between the flange of the can head and the can body andsoldered thereto, said tongue strip D being provided with an offset (Zand said can headflange having an offset or pocket b the simple corneruniting the flange and the flat or disk portion ofthe head itselfserving as the line of separation substantially as specified.

" JOHN LEE.

Witnesses:

H. M. MUNDAY, EDMUND ADOOCK.

